Preparation; Setting The Zero Calibration Value - HP 5890 Series II Plus Reference Manual

Electronic Flow Sensing
Electronic flow sensor (EFS) calibration

Preparation

1. Access the EFS by removing the left side panel; remove two screws
along its lower edge, slide the panel toward the rear of the
instrument, and then lift.
2. Through the keyboard, select CALIB AND TEST mode, function 2:
GAIN A is displayed, followed by two values: the observed flow rate
through Channel A, and the current gain calibration value for
Channel A.

Setting the zero calibration value

The zero calibration value must be set with no gas flow through the
channel being calibrated.
1. Press
current zero calibration value for EFS Channel A). Note that
Channel A is assumed by default; if channel B is to be calibrated
instead, press
2. Disconnect the gas source to the particular flow channel being
calibrated. Do not trust an on/off valve, pressure regulator, or mass
flow controller to be an effective shutoff device; any gas flowing
through the EFS will invalidate the zero calibration value.
Disconnect the source at any convenient point (e.g., at the connection
of the supply line into the instrument).
.
CLEAR
: FLOW A ZERO is displayed, followed by a value (the
ZERO
.
B
2 ENTER
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